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A disaster-resistant, point-to-multipoint network configuration that connects distributed optical terminals to a centralized optical terminal, through an exclusive fiber link, is required in edge computing strategies such as 5G, IoT applications, ultrareliable and low latency applications, high-performance content delivery, artificial intelligence applications, and hyperconverged infrastructure. Therefore, we introduce a shared link orientation that fully connects the distributed optical terminal side to the centralized optical terminal side represented by the conventional optical access network. We also propose a method that switches a fully-coupled or half-split network to the centralized optical terminal on the optical switch aggregation station side. We report a verification experiment on the proposed method to confirm the operation of wavelength conversion/optical path switching when a link failure occurs, achieving < 2 dB penalty with small back reflection in wavelength collision-free secondary link transmissions with primary link failure. The unique point of this research is that the centralized optical terminal can easily change from the link-occupancy-oriented network to the link-sharing-oriented network. This work will lead to development of a novel disaster-resistant network configuration for wavelength division multiplexing-based coherent passive optical network systems.
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Dirhodium(ii)-catalyzed ortho C-H amination of N,N-dialkylanilines has been developed. Sterically congested 1,2-diaminobenzenes were obtained in high yields with excellent chemo- and regioselectivities from para-substituted anilines and even from para-unsubstituted anilines. The ortho selectivity observed was rationalized in terms of the interaction between the dialkylamino group and a Rh(ii)-nitrene intermediate.
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Enhanced interferon α (IFNα) production has been implicated in the pathogenesis of systemic lupus erythematosus (SLE). We previously reported IFNα production by monocytes upon activation of the stimulator of IFN genes (STING) pathway was enhanced in patients with SLE. We investigated the mechanism of enhanced IFNα production in SLE monocytes. Monocytes enriched from the peripheral blood of SLE patients and healthy controls (HC) were stimulated with 2'3'-cyclic GAMP (2'3'-cGAMP), a ligand of STING. IFNα positive/negative cells were FACS-sorted for RNA-sequencing analysis. Gene expression in untreated and 2'3'-cGAMP-stimulated SLE and HC monocytes was quantified by real-time PCR. The effect of GATA binding protein 4 (GATA4) on IFNα production was investigated by overexpressing GATA4 in monocytic U937 cells by vector transfection. Chromatin immunoprecipitation was performed to identify GATA4 binding target genes in U937 cells stimulated with 2'3'-cGAMP. Differentially expressed gene analysis of cGAS-STING stimulated SLE and HC monocytes revealed the enrichment of gene sets related to cellular senescence in SLE. CDKN2A, a marker gene of cellular senescence, was upregulated in SLE monocytes at steady state, and its expression was further enhanced upon STING stimulation. GATA4 expression was upregulated in IFNα-positive SLE monocytes. Overexpression of GATA4 enhanced IFNα production in U937 cells. GATA4 bound to the enhancer region of IFIT family genes and promoted the expressions of IFIT1, IFIT2, and IFIT3, which promote type I IFN induction. SLE monocytes with accelerated cellular senescence produced high levels of IFNα related to GATA4 expression upon activation of the cGAS-STING pathway.
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Factor de Transcripción GATA4 , Expresión Génica , Interferón-alfa , Lupus Eritematoso Sistémico , Humanos , Factor de Transcripción GATA4/genética , Factor de Transcripción GATA4/metabolismo , Interferón Tipo I/metabolismo , Interferón-alfa/metabolismo , Lupus Eritematoso Sistémico/metabolismo , Monocitos/metabolismoRESUMEN
Treatment of PC12 cells with fungus-derived alkaloid neoechinulin A for more than 12 h renders the cells resistant to subsequent superoxide (O2â»)/nitric oxide (NO) insults derived from 3-morpholinosydnonimine (SIN-1). However, the underlying mechanism(s) remains largely unclear. To elucidate the mechanism(s), we assessed the specificity of the cytoprotection afforded by neoechinulin A treatment using other cytocidal stressors and also clarified the resulting cellular alterations, focusing on the antioxidant and metabolic enzymes systems. Neoechinulin A treatment for more than 12 h endowed PC12 cells with significant resistance to transient NO toxicity, but not persistent NO toxicity, bolus H2O2 toxicity, or oxidative insult from the redox cycling quinone menadione. Cellular antioxidant system profiling revealed no substantial potentiation of the activity of any antioxidant enzyme in lysate from the neoechinulin A-treated cells excluding glutathione (GSH) content, which was significantly decreased (>50%), resulting in a proportional compromise in the thiol-reducing activity of the intact cells. In addition, no differences were observed in the activity for any nicotinamide adenine dinucleotide (phosphate) reduced form (NAD(P)H)-generating enzyme, steady-state NAD(P)H/nicotinamide adenine dinucleotide (phosphate) oxidized form (NAD(P)âº) ratios, or the levels of total NAD(P)H. Nevertheless, the neoechinulin A-treated intact cells exhibited increased NAD(P)H redox turnover when driven by extracellular tetrazolium. The structurally inactive analog preechinulin failed to protect cells against NO toxicity or induce these alterations, suggesting their link with the cytoprotective mechanism. These results suggest that neoechinulin A, despite disabling the GSH defense system, confers cytoprotection against nitrosative stresses by elevating the cellular reserve capacity for NAD(P)H generation, which could offset crippling of energy-supplying systems due to nitrosative stress.
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Citoprotección/efectos de los fármacos , Alcaloides Indólicos/farmacología , Óxido Nítrico/toxicidad , Piperazinas/farmacología , Animales , Supervivencia Celular/efectos de los fármacos , Citoprotección/fisiología , Glutatión/metabolismo , Molsidomina/análogos & derivados , Molsidomina/farmacología , Nitrocompuestos/farmacología , Oxidación-Reducción , Estrés Oxidativo/efectos de los fármacos , Oxidorreductasas/metabolismo , Células PC12 , Ratas , ATPasa Intercambiadora de Sodio-Potasio/antagonistas & inhibidores , Transferasas/metabolismoRESUMEN
PURPOSE: To describe ocular complications in patients with human immunodeficiency virus (HIV) infection before and after highly active antiretroviral therapy(HAART). MATERIALS AND METHOD: We retrospectively reviewed the medical records of 261 patients who underwent HAART and visited our clinic between April, 2007 and March, 2010, and recorded ocular complications, CD4 cell counts, visual acuity and other relevant patient information. RESULTS: Befor HAART patients were found to have the following conditions: HIV retinopathy (41 cases), cytomegalovirus (CMV) retinitis (23 cases), and others (6 cases); and after HAART HIV retinopathy (5 cases), CMV retinitis (16 cases), Immune recovery uveitis(IRU) (4 cases), and others(9 cases). The average CD4+ T-cell counts at diagnosis of CMV retinitis were 45.2/microl before and 116.7/microl after HAART. CONCLUSIONS: Since a substantial number of patients develop CMV retinitis after the initiation of HAART, we need to examine patients to check for either the onset or reactivation of CMV retinitis and IRU even after HAART.
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Terapia Antirretroviral Altamente Activa , Retinitis por Citomegalovirus/epidemiología , Infecciones por VIH/tratamiento farmacológico , Enfermedades de la Retina/epidemiología , Uveítis/epidemiología , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Recuento de Linfocito CD4 , Retinitis por Citomegalovirus/etiología , Femenino , Infecciones por VIH/inmunología , Humanos , Masculino , Persona de Mediana Edad , Enfermedades de la Retina/virología , Estudios Retrospectivos , Factores Sexuales , Uveítis/etiología , Adulto JovenRESUMEN
PURPOSE: To compare the shape of the anterior segment of eyes with keratoconus and normal controls using anterior segment optical coherence tomography (AS-OCT). SUBJECTS AND METHODS: Included in the study were eyes with keratoconus (60 eyes of 40 patients), eyes with suspected keratoconus (10 eyes of 10 patients), and normal controls (21 eyes of 13 persons). Anterior segment imaging was performed in these eyes with AS-OCT, and the distance for angle to angle, anterior chamber depth and distribution of corneal thickness including the increasing ratio from center to periphery were compared. RESULTS: There was no significant difference in the distance of angle to angle among the three groups. The ratio of eyes with anterior chamber depth of more than 3.6 mm in the eyes with keratoconus was significantly higher than in the normal group. Although the corneal thickness from the center to the 3 mm periphery in the keratoconus group and in the keratoconus suspect group was significantly thinner than those in the normal group, there were no significant differences in the corneal thickness at the 4 mm superior or temporal areas among the three groups. Increasing ratio of the corneal thickness from the center to the periphery showed the higher value in the keratoconus group than in the others. CONCLUSION: AS-OCT enabled us to understand the configuration of the anterior segment of the eye and the distribution of the corneal thickness quantitatively even for the advanced keratoconus cases with corneal scar. AS-OCT may be useful as an aid to contact lens prescription and surgical planning.
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Cámara Anterior/patología , Queratocono/patología , Tomografía de Coherencia Óptica , Adulto , Femenino , Humanos , MasculinoRESUMEN
Poorly absorbable sugar alcohols (e.g., mannitol, sorbitol, and maltitol) are the excipients frequently contained in pediatric dosage forms. Due to their osmotically active properties, certain amount of sugar alcohols reportedly reduces oral bioavailability of concomitant drugs. This fact implies the possible pharmacokinetic interaction between orally administered drug and sugar alcohols which are present in other concomitant medications. The purpose of this study was to identify the possibility and likeliness of the osmotically active excipient-induced pharmacokinetic interaction in pediatric polypharmacy. Previously developed in silico model that captured the osmotic effect of sugar alcohols in adults was expanded to pediatric population. This mathematical model successfully explained the impaired bioavailability of lamivudine by the co-administered sorbitol in other dosage forms. In the meantime, sugar alcohol contents in marketed pediatric dosage forms were investigated by reverse engineering technology. Considering the critical administration dose of sugar alcohols estimated by in silico model, it was revealed that 25 out of 153 pediatric dosage forms were identified as possible perpetrators even under the approved administration and dosage in Japan. This study shed light on the potential pharmacokinetic interaction that cannot be dismissed throughout the pediatric pharmaceutical dosage form design and development.
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Excipientes , Preparaciones Farmacéuticas , Administración Oral , Adulto , Disponibilidad Biológica , Niño , Humanos , Ósmosis , PolifarmaciaRESUMEN
PURPOSE: To assess the ability of a newly developed 193 nm solid-state laser to ablate the cornea. SETTING: Osaka University, Osaka, Japan. METHODS: A prototype laser engine was developed by combining a 1547 nm laser diode, fiber amplifiers, and 5 stages of a frequency-conversion system using CsLiB6O10 crystals as the last stage. Poly(methyl methacrylate) (PMMA) plates were exposed to the prototype laser beam to determine the relationship between the fluence and ablation rate. Laser irradiation of porcine corneas was performed to induce morphological changes, and the quality of the lesions was determined by light and scanning electron microscopy. RESULTS: The relationship between the fluence and ablation rate of the 193 nm solid-state laser was comparable to that of the argon-fluoride excimer laser. Light and scanning electron microscopy of the porcine corneas showed that the linear and square lesions had sharp, clean edges. CONCLUSIONS: Smooth ablations of PMMA plates and porcine corneas were obtained by the laser. Further investigations must be conducted to determine whether this laser can be an alternative laser source for keratorefractive surgery.
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Córnea/cirugía , Láseres de Estado Sólido/uso terapéutico , Procedimientos Quirúrgicos Refractivos/instrumentación , Animales , Córnea/ultraestructura , Diseño de Equipo , Microscopía Electrónica de Rastreo , Polimetil Metacrilato , PorcinosRESUMEN
PURPOSE: To evaluate visual function disorder in patients with branch retinal vein occlusion by quantifying the degree of metamorphopsia. DESIGN: prospective interventional case series. SUBJECTS AND METHODS: The subjects were 12 patients(12 eyes) whose fovea was involved with branch retinal vein occlusion within a month after noticing their symptoms. The best-corrected visual acuity, and vertical and horizontal metamorphopsia scores were obtained within one month, and at 3 months and 6 months after the onset of symptoms regardless of therapy. The metamorphopsia scores were measured with M-CHARTS. RESULTS: Although the average best-corrected visual acuity at 6 months was significantly better than that within a month of noticing symptoms, the average metamorphopsia scores did not improve after 6 months, and were not related to the average best-corrected visual acuity in either vertical or horizontal lines. CONCLUSIONS: The degree of metamorphopsia measured with M-CHARTS is an important parameter in addition to the best-corrected visual acuity for evaluating visual function in patients with branch retinal vein occlusion.
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Técnicas de Diagnóstico Oftalmológico , Oclusión de la Vena Retiniana/diagnóstico , Oclusión de la Vena Retiniana/fisiopatología , Visión Ocular , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores de Tiempo , Agudeza VisualRESUMEN
PURPOSE: To investigate the possible factors involved in the development of acute hydrops in patients with keratoconus. DESIGN: Prospective interventional case series. METHODS: Thirteen consecutive keratoconic eyes of 13 patients with acute hydrops were examined by ultrasound biomicroscopy (UBM). RESULTS: Ultrasound biomicroscopy (UBM) examinations revealed a rupture of Descemet membrane and intrastromal clefts in all eyes. In 11 of 13 eyes, the intrastromal clefts were connected to the anterior chamber. CONCLUSIONS: Formation of intrastromal clefts may be an important factor in the development of acute hydrops in keratoconic eyes. The clefts may cause severe corneal edema and delay the closure of Descemet membrane during the resolution of corneal edema.
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Edema Corneal/diagnóstico por imagen , Lámina Limitante Posterior/lesiones , Queratocono/diagnóstico por imagen , Microscopía Acústica , Enfermedad Aguda , Adolescente , Adulto , Edema Corneal/etiología , Lámina Limitante Posterior/diagnóstico por imagen , Femenino , Humanos , Queratocono/complicaciones , Masculino , Estudios Prospectivos , RoturaRESUMEN
PURPOSE: We quantified the chronologic progression of keratoconus using anterior segment optical coherence tomography (AS-OCT). METHODS: A total of 217 eyes from 113 patients with keratoconus, keratoconus suspect, or forme fruste keratoconus were evaluated by corneal tomography using swept-source OCT. Age-dependent changes in the radius of the posterior best-fit sphere (Rpost), minimum corneal thickness (Tmin), and distance from the thinnest point to the corneal vertex (Dmin) were examined over follow-up periods of up to 5.79 years and were analyzed using generalized estimating equation (GEE) nonlinear regression model. RESULTS: Annual changes in Rpost (mean, -0.017 mm) and Tmin (-2.69 µm) were significantly higher in younger patients (P < 0.01, GEE nonlinear regression) and in patients with higher maximal K value (Kmax; P < 0.01, GEE nonlinear regression), whereas no changes were observed in Dmin. Even in patients 30 years or older, 14% of eyes revealed remarkable progression in Rpost. In eyes with acute hydrops, annual changes in Rpost (-0.22 mm) and Tmin (-33.8 µm) before acute corneal hydrops were more than 10 times faster than those in other eyes (P < 0.001, GEE nonlinear regression). CONCLUSIONS: Chronologic measurements of corneal tomography in keratoconus demonstrated that the progression of steepening at posterior corneal surface was found not only in patients under 30 years but also in older patients, particularly in advanced keratoconus. The rate of progression can be measured by mapping of corneal curvature and thickness using OCT, and the risk of progression was greater in younger patients with steeper Kmax.
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Córnea/patología , Imagenología Tridimensional/métodos , Queratocono/diagnóstico , Tomografía de Coherencia Óptica/métodos , Adolescente , Adulto , Anciano , Topografía de la Córnea/métodos , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Análisis de Regresión , Estudios Retrospectivos , Factores de Tiempo , Adulto JovenRESUMEN
Vogt-Koyanagi-Harada (VKH) disease and central serous chorioretinopathy (CSC) develop serous retinal detachment; however, the treatment of each disease is totally different. Steroids treat VKH but worsen CSC; therefore, it is important to distinguish these diseases. Here, we report a case with CSC which was diagnosed by en face optical coherence tomography (OCT) imaging during the course of VKH disease. A 50-year-old man was referred with blurring of vision in his right eye. Fundus examination showed bilateral optic disc swelling and macular fluid in the right eye. OCT showed thick choroid, and en face OCT images depicted blurry choroid without clear delineation of choroidal vessels. Combined with angiography findings, this patient was diagnosed with VKH disease and treated with steroids. Promptly, fundus abnormalities resolved with the reduction of the choroidal thickness and the choroidal vessels became visible on the en face images. During the tapering of the steroid, serous macular detachment in the right eye recurred several times. Steroid treatment was effective at first; however, at the fourth appearance of submacular fluid, the patient did not respond. At that time, the choroidal vessels on the en face OCT images were clear, which significantly differed from the images at the time of recurrence of VKH. Angiography also suggested CSC-like leakage. The tapering of the steroids was effective in resolving the fluid. Secondary CSC may develop in the eye with VKH after steroid treatment. En face OCT observation of the choroid may be helpful to distinguish each condition.
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PURPOSE: We sought to assess the corneal thickness of the epithelium and stroma in keratoconic and normal eyes by spectral-domain optical coherence tomography (SD-OCT). METHODS: Fifty-seven keratoconic and 20 normal eyes were studied. The eyes were examined by SD-OCT, and the keratoconic eyes were subdivided into 2 groups: those showing only smooth corneal thinning and corneal protrusion on the image (KC1 group) and those showing abnormalities in the Bowman layer or in the stroma, or in both (KC2 group). The thicknesses at the corneal vertex and at the superior, inferior, nasal, and temporal cornea 1.5 mm from the corneal vertex in the KC1 group were compared with those in the normal group. The OCT findings in the KC2 group were described. RESULTS: The epithelial thickness at the corneal vertex and at the inferior and temporal cornea, and the stromal thickness at all points were significantly thinner in the KC1 group than in the normal group (p < 0.05). The epithelial and stromal thicknesses at the corneal vertex were significantly correlated in the KC1 group and the normal group (r (2) = 0.427, p < 0.0001).The epithelial thickness in the KC2 group was not uniform owing to Bowman layer scarring, stromal scars, and secondary corneal amyloidosis. CONCLUSIONS: Although epithelial thinning is associated with stromal thinning, when the cornea remains clear, the epithelial thickness may vary because of the irregularity of the stroma beneath the epithelium in patients with keratoconus.
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Sustancia Propia/patología , Epitelio Corneal/patología , Queratocono/patología , Adulto , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Tomografía de Coherencia Óptica , Adulto JovenRESUMEN
PURPOSE: We investigated higher-order aberrations (HOAs) of the anterior and posterior corneal surfaces in patients with keratectasia after LASIK. METHODS: The subjects comprised four groups: 12 eyes with keratectasia after LASIK, 30 eyes following LASIK without keratectasia, 30 keratoconic eyes, and 30 normal eyes. Corneal HOAs due to the anterior and posterior corneal surfaces for 6-mm pupils (root mean square [µm]) were obtained using a Scheimpflug-based corneal tomographer and compared among the four groups. RESULTS: There were significant differences in total HOAs of the anterior and posterior corneal surfaces (mean ± SD) in the keratectasia (2.49 ± 1.37 and 0.83 ± 0.57), keratoconus (4.50 ± 2.57 and 1.18 ± 0.65), LASIK (0.84 ± 0.25 and 0.14 ± 0.04), and normal (0.52 ± 0.15 and 0.17 ± 0.06) groups except for between keratoconus and keratectasia at the posterior surface. Keratectasia and keratoconus showed similar coma-dominant patterns at both surfaces, and there were no significant differences in the Zernike terms between both groups except for the total HOAs and coma aberration at the anterior surface. CONCLUSIONS: Although flap creation and laser ablation were supposed to center on the primary line of sight in LASIK, keratectasia after LASIK showed coma-dominant HOAs at both corneal surfaces. This suggests that the cornea in keratectasia has optical properties similar to those in keratoconus.
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Aberración de Frente de Onda Corneal/diagnóstico , Endotelio Corneal/patología , Epitelio Corneal/patología , Queratocono/diagnóstico , Queratomileusis por Láser In Situ , Láseres de Excímeros/uso terapéutico , Complicaciones Posoperatorias , Aberrometría , Adulto , Dilatación Patológica/diagnóstico , Dilatación Patológica/etiología , Femenino , Humanos , Imagenología Tridimensional , Queratocono/etiología , Masculino , Miopía/cirugía , Fotograbar , Estudios RetrospectivosRESUMEN
With the increasing popularity of selective lamellar keratoplasty procedures, it is important to characterize the optical differences among penetrating keratoplasty (PK), deep anterior lamellar keratoplasty (DALK), and Descemet stripping automated endothelial keratoplasty (DSAEK). The impact of optical differences on the visual acuity (VA) in eyes after keratoplasty is significant. Quantitative evaluation of corneal higher-order aberrations (HOAs) of anterior and posterior surfaces using a rotating Scheimpflug-based corneal topographer, showed that eyes that undergo DSAEK have lower anterior corneal HOAs compared with eyes subjected to PK or DALK. In DSAEK, the anterior corneal surfaces are not replaced, which is in contrast to PK or DALK, where they are replaced. Through evaluation of corneal scatter with a densitometry program associated with the rotating Scheimpflug-based corneal topographer, 3 characteristic patterns of corneal scatter were found in eyes that had undergone keratoplasty. Investigation of the impact of corneal HOAs and corneal scatter on VA after keratoplasty showed that the VA was correlated significantly with corneal scatter.
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Córnea/fisiopatología , Trasplante de Córnea , Queratoplastia Endotelial de la Lámina Limitante Posterior , Queratoplastia Penetrante , Visión Ocular/fisiología , Enfermedades de la Córnea/fisiopatología , Enfermedades de la Córnea/cirugía , Topografía de la Córnea , Aberración de Frente de Onda Corneal/fisiopatología , Humanos , Luz , Dispersión de RadiaciónRESUMEN
PURPOSE: To investigate the characteristics of the corneal topography with three-dimensional (3-D) anterior segment optical coherence tomography (AS-OCT) following Descemet's stripping automated endothelial keratoplasty (DSAEK). METHODS: Thirty-four eyes of 33 patients following DSAEK were studied. In addition to conventional topographic maps, the elevation map of the intrastromal interface and pachymetric maps of the host and graft were obtained by corneal topographic analysis using 3-D AS-OCT. The coefficient of variation of the corneal power (CV-Pa, CV-Pp) and root mean squares of the corneal elevation (RMS-Ea, RMS-Ep) of the anterior and posterior corneal surfaces were determined. Based on the combination of the regularity and irregularity of the anterior and posterior surfaces, subjects were classified into four types: type 1, regular/regular; type 2, irregular/regular; type 3, regular/irregular; and type 4, irregular/irregular. RESULTS: The average graft decentration was 0.59 ± 0.23 mm. The proportion of types 1, 2, 3, and 4 were 59%, 9%, 24%, and 9 %, respectively. The CV-Pa (25.8 ± 8.9) and CV-Pp (-73.9 ± 18.0) of the type 1 corneas were significantly better than that of type 2 and type 3 corneas, respectively. The RMS-Ea (5.1 ± 1.3) and RMS-Ep (26.0 ± 7.3) of the type 1 corneas were significantly better than that of type 2 and type 3 corneas. CONCLUSIONS: An OCT-based corneal topographer might be useful in determining the factors associated with optical quality of the cornea following DSAEK by analyzing the topographic characteristics of host and donor separately.
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Córnea/patología , Enfermedades de la Córnea/cirugía , Topografía de la Córnea/métodos , Queratoplastia Endotelial de la Lámina Limitante Posterior/métodos , Imagenología Tridimensional , Tomografía de Coherencia Óptica/métodos , Anciano , Córnea/cirugía , Enfermedades de la Córnea/patología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Reproducibilidad de los ResultadosRESUMEN
PURPOSE: To investigate the corneal higher-order aberrations (HOAs) of the anterior and posterior corneal surfaces in eyes that underwent penetrating keratoplasty (PK), deep anterior lamellar keratoplasty (DALK), and Descemet stripping automated endothelial keratoplasty (DSAEK). DESIGN: Retrospective, case-control study. METHODS: study population: Twenty-four eyes underwent PK, 28 eyes underwent DALK, and 19 eyes underwent DSAEK; 29 normal eyes served as controls. observation procedures: The anterior and posterior corneal heights and pachymetric data were obtained with a Scheimpflug-based corneal topographer. Corneal HOAs for 4-mm pupils were calculated from the height data and were expanded with normalized Zernike polynomials. The HOAs resulting from the anterior and posterior corneal surfaces were compared among the procedures. main outcome measures: Anterior and posterior corneal HOAs (root mean square). RESULTS: Control eyes had significantly lower total HOAs and Zernike vector terms of the anterior and posterior surfaces than the other groups, except for spherical aberration. The mean anterior corneal surface total HOAs in the PK, DALK, DSAEK, and control groups were 1.38 ± 0.67 µm, 1.19 ± 0.57 µm, 0.61 ± 0.33 µm, and 0.21 ± 0.07 µm, respectively. The anterior corneal HOAs in the DSAEK group were significantly less than those in the PK group (P < .001) and DALK group (P < .001). The mean posterior corneal surface total HOAs were, respectively, 0.20 ± 0.09 µm, 0.24 ± 0.11 µm, 0.27 ± 0.15 µm, and 0.07 ± 0.02 µm. There were no significant differences in the posterior corneal HOAs among the treatment groups. CONCLUSIONS: Because the refractive indices between the anterior and the posterior surfaces differed greatly, eyes that undergo DSAEK have lower anterior corneal HOAs compared with PK or DALK eyes. However, the anterior and posterior corneal HOAs in DSAEK eyes still were greater than those in control eyes.
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Trasplante de Córnea , Aberración de Frente de Onda Corneal/fisiopatología , Queratoplastia Endotelial de la Lámina Limitante Posterior , Endotelio Corneal/fisiopatología , Epitelio Corneal/fisiopatología , Queratoplastia Penetrante , Anciano , Estudios de Casos y Controles , Enfermedades de la Córnea/cirugía , Topografía de la Córnea , Humanos , Persona de Mediana Edad , Estudios RetrospectivosRESUMEN
PURPOSE: To assess a new corneal topographer based on 3-dimensional anterior segment optical coherence tomography (OCT-based corneal topographer) for analyzing corneal topography in patients with keratoconus. SETTING: Osaka University Graduate School of Medicine, Osaka, Japan. DESIGN: Evaluation of diagnostic test or technology. METHODS: Keratoconic eyes and normal control eyes were assessed using a rotating Scheimpflug-based corneal topographer and an AS OCT-based corneal topographer. The OCT-based corneal topographer, a 1310 nm swept-source device, captures 8192 points during 0.34 second for 16 radial scans of the corneal topography. The success rate of precisely digitizing the corneal surfaces, patterns of the color-coded maps, central corneal thickness (CCT), and central axial power were compared between the 2 devices. RESULTS: Forty keratoconic eyes and 30 control eyes were assessed. The OCT-based corneal topographer measured corneal configurations despite corneal opacities. The success rate of precisely digitizing the corneal surfaces in keratoconic eyes was 95% using OCT and 80% using the Scheimpflug-based corneal topographer. The color-coded maps of the anterior and posterior corneal elevations, CCT, and corneal axial power maps generated by the 2 devices agreed well. The correlations between the CCT values and between the central corneal axial power values measured by the 2 devices were well correlated in both groups. CONCLUSIONS: The OCT-based corneal topographer, with its faster acquisition time, provided more consistent measurements than the Scheimpflug-based corneal topographer. The OCT-based corneal topographer seems promising for evaluating highly irregular corneas, as in cases of advanced keratoconus. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.
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Córnea/patología , Topografía de la Córnea/instrumentación , Imagenología Tridimensional , Queratocono/diagnóstico , Tomografía de Coherencia Óptica/instrumentación , Adulto , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , MasculinoRESUMEN
PURPOSE: This study was designed to investigate higher-order aberrations (HOAs) due to the posterior corneal surface in keratoconic eyes compared with normal eyes. METHODS: We studied 24 normal and 28 keratoconic eyes. The anterior/posterior corneal heights and pachymetric data were obtained with a rotating Scheimpflug camera. HOAs for 6 mm pupils were calculated from the differences between the height data and the best-fit sphere, using an original program for each corneal surface. The reference axes of the measurements were aligned with the primary line of sight. The HOAs were expanded with normalized Zernike polynomials. For each pair of standard Zernike terms for trefoil, coma, tetrafoil, and secondary astigmatism, one value for the magnitude and axis was calculated by Zernike vector analysis. RESULTS: The mean total corneal HOAs (root mean square [microm]) from the anterior/posterior surfaces were significantly (P < 0.001) higher in keratoconic (4.34/1.09, respectively) than in control eyes (0.46/0.15). The mean magnitude of each Zernike vector terms for trefoil, coma, and spherical aberration from the anterior/posterior surfaces was significantly (P < 0.001) higher in keratoconic (0.77/0.19, 3.57/0.87, -0.44/0.17) than control eyes (0.09/0.04, 0.33/0.07, 0.25/-0.07), respectively. The mean axes by vector calculation for coma due to the anterior (63.6 degrees ) and posterior surfaces (241.9 degrees ) were in opposite directions. CONCLUSIONS: Corneal HOAs on both corneal surfaces in keratoconic eyes were higher than in control eyes. Coma from the posterior surface compensated partly for that from the anterior surface. Residual irregular astigmatism in patients with keratoconus wearing rigid gas permeable contact lenses can be estimated by measuring the HOA from the posterior corneal surface.
Asunto(s)
Astigmatismo/fisiopatología , Endotelio Corneal/patología , Queratocono/fisiopatología , Adulto , Astigmatismo/diagnóstico , Topografía de la Córnea , Femenino , Humanos , Queratocono/diagnóstico , Masculino , Fotograbar , Refracción Ocular/fisiologíaRESUMEN
A novel intragastric floating drug delivery system (FDDS) has been prepared by pulsed plasma-irradiation on the double-compressed tablet of 5-Fluorouracil (5-FU) as a core material with outer layer composed of a 68/17/15 weight ratio of Povidone (PVP), Eudragit RL (E-RL) and NaHCO3. The plasma heat flux caused the thermal decomposition of NaHCO3 to generate carbon dioxide and the resultant gases were trapped in bulk phase of outer layer, so that the tablets turned to have a lower density than the gastric contents and remained buoyant in simulated gastric fluid for a prolonged period of time. In addition, the release of 5-FU from the tablet is sustained by occurrence of plasma-induced crosslink reaction on the outer layer of tablet and the release rate of 5-FU can be well controlled by plasma operational conditions.